Topic 2-organisation Flashcards
what are cells?
Cells are the basic building blocks that make up all living organisms.
what are tissues?
A tissue is a group of similar cells working together to perform a particular function.
what is an organ?
An organ is a group of different tissues working together to peform a particular function
What is an organ system?
An organ system is a group of organs working together to perform a particular function.
what is an enzyme?
An enzyme is a biological cataylst.
what is the purpose of the mouth(salivary glands)?
mechanical digestion–>produces enzyme amalayse in saliva
what is the purpose of the oesophagus?
tube that connects the mouth to the stomach
what is the purpose of the liver?
Produces bile:
->Bile neutralises stomach acid
->bile emulsifies fats
what is the purpose of the stomach?
mixes food and drink with acid to break it down
what is the purpose of the pancreas?
produces all three digestive enzymes which are then secreted into the small intestine
what is the purpose of the gall bladder ?
stores bile before releasing it into the first section of the small intestine
what is the purpose of the bile duct?
takes bile from the gall bladder to first section of the small intestine
what is the purpose of the small intestine?
->digested food is absorbed out of the digestive system into the blood
what is the purpose of the large intestine?
->where excess water is absorbed from the food
what is the prupose of rectum/anus?
->the faeces are stored in the rectum before they are excreted through the anus
Define a catalyst:
A cataylst is a substance which increases the speed of a reaction without being changed or used up in the reaction.
what are enzymes made up of?
Enzymes are made up of proteins which are chains of amino acids.
what is the role of digestive enzymes?
Digestive enzymes convert food into small soluble molecules that can be absorbed into the bloodstream.
Describe the lock and key model
1)The active site has a complimentaryshape to the substrate
2)Substrate collides with active site of enzyme and becomes attached to make an enzyme-substarte complex
3)Enzyme catalyses break down of substrate
4)Products are released from active sight
what is the induced fit model?
In reality,the active sight changes shape a little as the substrate binds to it to get a tighter fit which froms an induced-fit complex.
what does it mean when an enzyme becomes denatured?
An enzyme is denatured when the shape of the active sight has been changed so that the substrate won’t fit anymore.
what is an optimal condition?
AN optimal conditiopn is the conditions needed for an enzyme to work best at
Name x2 optimal conditions
->temperature
->PH
what is it called if an enzyme speeds up the rate of reaction?
enzyme-catalysed reaction
how does temperature increase the rate of reaction in an enzyme?
->The thermal energy heats up the enzyme causing the kinetic energy of the enzyme to increase causing more collisions between enzyme and substrate
->This causes an increase in enzyme activity therfore more formation of enzyme/substarte complexes.
->An increase in temperaure beyond optimum decreases enzyme activity–>enzyme becomes denatured
how does PH level affect an enzyme?
->when the PH increases so does the rate of enzyme activity
->An optimum activity is reached at the enzymes’s optimum
->after the enzyme reaches its optimum the enzymes active site changes shape some of the bonds start to break
->this causes the active sight to lose shape
->the active sight changes so muchthat the enzyme becomes denatured as the enzyme can no loner bind to the substarte.
how does subtsrate concentration affect an enzyme?
->as the substrate concentration increases so does enzyme activity
->this is because more enzymes can form enzyme-substrate complexs.
->An optimum rate is reached at the enzymes optimum substrate concentration
->A continued increase results in the same activity as there are not enough enzyme molecules available to break down excess substrate molecules.
what do carbohydrases do?
carbohydrases convert carbohydrates into simple sugars.
Name the word equation for amalyse:
Starch————->maltose
amylase
what does protease do?
protease breaks down proteins into amino acids
Name the word equation for protease:
proteins————->amino acids
protease
what does lipase do?
lipase breaks down a lipid into glycerol and fatty acids
Name the word equation for lipase
lipid——->fatty acids+glycerol
lipase
what x 3 places is amylase made
->the salivary glands
->the pancreas
->the small intestine
what x 3 places is protease made?
->the stomach
->the pancreas
->the small intestine
what x 2 places are lipase made?
->the pancreas
->the small intestine
Name what the stomach produces and what it does:(hint:acid)
The stomach produces hydrochloric acid(x2 reasons):
–»to kill bacteria
–>to give optimal PH conditions for enzyme protease(pepsin) to work
Around what PH does pepsin in the stomach work best at?
The stomach works best at around PH 2
what does the liver produce and what it does:
The liver produces bile:
->bile (alkaline)neutralises stomach acid to make conditions alkaline for enzymes in the small intestine to work best at.
->emulsifies fats(breaks down the fat into tiny droplets)to increase the surface area for the enzyme lipase to work on which makes the rate of digestion faster.
how to prep a food sample?
->get a peice of food and break it up using a pestle and mortar
->trasnfer ground up food to a beaker and add some distilled water
->give mixture a stir using a glass rod to dissolve some food
->filter solution using a funnel lined with filter paper to get rid of solid bits
Describe benedicts test for reducing sugars
->prep a food sample and transfer 5cm cubed to a test tube
->prepare a waterbath set to 75 degrees celcius
->add some benedicts solution to test tube using pipette(10 drops)
->place test tube in water bath using a test tube holder/leave for 5 mins
what would you get as a P/N result for benedicts test?
N-solution stays blue
P-green->low reducing sugars
yellow->moderate reducing sugars
brick-red->high reducing sugars
Describe Iodine test for starch
->make a food sample and trasfer 5 cm cubed to a test tube
->add a few drops of iodine solution
->gently shake tube to mix contents
What would you get a P/N result for Iodine test?
N-stays browny-orange
P-turns from browny-orange to black/blue-black
Describe Buriet test
->prepare a sample of food and transfer 2 cm cubed to a test tube
->add 2cm cubed of buiret solution
->mix contents by gently shaking tube
what is a P/N test for buiret solution?
N-solution stays blue
P-solutions turns from blue to purple
